1. Field of the Invention
This invention relates to industrial size, multi-level water cooling towers of the type having upper and lower film fill packs arranged one above the other, and wherein a self-balancing hot water distribution system is provided for delivering water from a main supply line to hot water distributors overlying the upper and lower fill packs respectively for directing hot water across the top of each of the packs.
2. Description of the Prior Art
U.S. Pat. No. 4,826,636, assigned to the assignee hereof, illustrates and describes a multi-level film fill industrial cross flow cooling tower having a series of film fill packs arranged in vertically spaced and horizontally offset relationship. The hot water distribution system of the tower in the '636 patent includes a hot water distribution basin overlying the uppermost fill pack for delivering hot water over the top of that pack, and piping leading from the main supply line to a hot water distribution basin directly over the next lower fill pack.
In instances where more than three vertically spaced fill packs are employed, each fill pack below the uppermost fill has piping means for delivering hot water from the main supply line into a distribution basin directly over respective lower fill packs.
Although this system embodied advantageous features over then existing cooling tower art, and particularly as replacement structure for splash type fill structure, the hot water distribution system did not provide for differences in the flow of hot water through the main supply line. Although not detailed in the '636 patent, those skilled in the art understand that appropriate valve means could be provided for selectively controlling the flow of hot water into the distributors overlying respective fill packs, to compensate for variations in the flow of hot water through the main supply line.
However, manually operating such valves in a manner to obtain an even flow of hot water to each of the distributors overlying the multi-level film fill packs is a time consuming and sometimes difficult task, particularly when it is recognized that industrial size towers of the type shown and described in the '636 patent generally have at least two or three cells and may have as many as twelve or more cells. Thus, these towers are tens of feet high and may be hundreds of feet long. Personnel would therefore be required to adjust and readjust the valves until a required flow into each distributor was obtained. This would mean walking up and down the length of the tower a number of times, or provision of a large crew using radio communications. Even then, difficulties would be encountered in obtaining a balanced water flow into the various distributors overlying respective film fill packs, with valve changes being required each time there was a variation in the flow of hot water through the main supply line.